This invention relates to an improved system for maintaining a desired quantity of clean oil in a lubrication system for an internal combustion engine, especially a diesel fuel engine.
Prior versions of such a system of which the present invention is an improvement are disclosed in two of my prior patents, U.S. Pat. Nos. 4,421,078 and 4,495,909. These systems both employ a cylinder having a solid piston which pumps a preloaded quantity of lubricant extracted from an oil pan of an internal combustion engine into a fuel return line. Two or more solenoids are utilized in each system to regulate the flow of air and lubricant into the cylinder.
Devices illustrative of the art since issuance of the latter of the above-cited patents include that taught in U.S. Pat. No. 4,869,346 to Nelson, which discloses a system for automatically changing engine lubricating oil while an internal combustion engine is running. A double-acting displacement unit in the system periodically extracts an amount of used oil from the engine lubricating system and pumps the amount to either a diesel fuel tank or to a crankcase of the engine, depending on the level of oil within the crankcase as detected by dipstick-mounted sensing means. Fresh oil is withdrawn from an oil reservoir and pumped to the crankcase. This system likewise employs a plurality of solenoids. An LED malfunction light on a controller signals potential failure of any such solenoid, as well as that of the displacement unit, upon an abnormally long time lapse between cycles. Although such an arrangement indicates improper operation, there is no means disclosed for confirming proper working order of the system so as to reduce the likelihood of a malfunction in the first place.
Further illustrative of the art is the device disclosed in U.S. Pat. Nos. 4,572,120 and 4,615,305 to Matsumoto, in which an outboard motor is provided with a lubricant delivery tank mounted thereon receiving lubricant from a remotely-positioned storage tank and delivering it to a pump whereby it is fed into the intake manifold of the motor. The pump does not, however, pump lubricant in predetermined quantities, nor is it actuated at regular periodic intervals. The disclosed system additionally possesses the shortcomings discussed previously with regard to other known systems.
It has been found desirous to implement a testing mode for an oil cleaning and recycling system such that one may visually confirm that the system is in working order prior to transit of the rig upon which the system is mounted. No mechanism permitting such testing has been heretofore known. Moreover, it has been found advantageous to minimize the number of solenoids in an oil cleaning and recycling system.